Despite the lack of rain, the green manures sown after the harvest are finally starting to come up well, here in a plot of Alicante Bouschet (the grape variety used in our Trois Nuits cuvée):
The mixture sown this year included oats, barley, vetch and chickling vetch.
Green manuring is one of the most important agro-ecological practices, providing numerous benefits that all contribute to improving soil fertility:
- Improved soil life: plant cover protects the soil from extreme temperatures and maintains a certain level of humidity, thus facilitating the development of numerous micro-organisms.
- Protection against erosion: plant cover prevents the soil from being washed away by the heavy rains we sometimes receive.
- Improved soil structure thanks to root development. Some of the species in the mixtures are chosen for the quality of their root systems, which break up the soil deep down.
- Nutrient contribution: legumes (vetch, chickling vetch, faba bean, etc.) fix atmospheric nitrogen and return it to the soil. Decomposition of the plant cover by soil micro-organisms also releases numerous trace elements that enrich organic matter and soil fertility.
The species sown are also chosen for the quantity of biomass they can produce between sowing and destruction, the aim being to have a large volume of organic matter deposited on the soil surface by the time the cover is destroyed in spring.
The decomposition of this biomass by soil micro-organisms will reconstitute the soil's humus and enrich its organic matter, as in a forest soil, thus activating the crop's natural fertilization processes (rather than applying synthetic mineral fertilizers that short-circuit and consequently kill soil life, transforming it into an inert, compact and erodible substrate).
Some species can even help us fight certain pathogens. For example, barley prevents the development of root rot, a fungus that attacks the roots of vines and fruit trees.
Here's another photo of this year's green manures, this time in our Aramon plot: